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We place new constraints on the primordial local non-Gaussianity parameter f_NL using recent Cosmic Microwave Background anisotropy and galaxy clustering data. We model the galaxy power spectrum according to the halo model, accounting for a…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Francesco De Bernardis , Paolo Serra , Asantha Cooray , Alessandro Melchiorri

We develop and study the position-dependent bispectrum. It is a generalization of the recently proposed position-dependent power spectrum method of measuring the squeezed-limit bispectrum. The position-dependent bispectrum can similarly be…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-02 Saroj Adhikari , Donghui Jeong , Sarah Shandera

Recent analysis of the WMAP three year data suggests $f_{NL}^{local}\simeq86.8$ in the WMAP convention. It is necessary to make sure whether general single field inflation can produce a large positive $f_{NL}$ before turning to other…

Astrophysics · Physics 2009-06-23 Miao Li , Tower Wang , Yi Wang

During inflation, massive fields can contribute to the power spectrum of curvature perturbation via a dimension-5 operator. This contribution can be considered as a bias for the program of using $n_s$ and $r$ to select inflation models.…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-06 Hongliang Jiang , Yi Wang

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of…

The 21-cm brightness temperature fluctuation from the Dark Ages ($z \simeq 30-100$) will allow us to probe the inflationary epoch on very small scales ($>0.1 \, \mbox{Mpc}^{-1}$), inaccessible to cosmic microwave background experiments.…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-28 Giorgio Orlando , Thomas Flöss , P. Daniel Meerburg , Joseph Silk

The recently released BICEP2 data detected the primordial B-mode polarization in the Cosmic Microwave Background (CMB) map which strongly supports for a large tensor-to-scalar ratio, and thus, is found to be in tension with the Planck…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-30 Youping Wan , Siyu Li , Mingzhe Li , Taotao Qiu , Yifu Cai , Xinmin Zhang

In light of the most recent cosmological observations, we provide new updated constraints on the slow-roll inflation in different extended scenarios beyond the $\Lambda\rm{CDM}$ cosmological model. Along with the usual six parameters, we…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-25 Matteo Forconi , William Giarè , Eleonora Di Valentino , Alessandro Melchiorri

A minimal extension of the Standard Model (SM) with a single new mass scale and providing a complete and consistent picture of particle physics and cosmology up to the Planck scale is presented. We add to the SM three right-handed…

High Energy Physics - Phenomenology · Physics 2017-02-22 Guillermo Ballesteros , Javier Redondo , Andreas Ringwald , Carlos Tamarit

To efficiently probe primordial non-Gaussianity using Cosmic Microwave Background (CMB) data, we require theoretical predictions that are factorizable, \textit{i.e.}\ those whose kinematic dependence can be separated. This property does not…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-25 Oliver H. E. Philcox , Kunhao Zhong , Salvatore Samuele Sirletti

We present the first direct constraints on a Degenerate Higher Order Scalar Tensor (DHOST) inflation model using the Planck 2018 Cosmic Microwave Background (CMB) results on non-Gaussianities. We identify that the bispectrum consists of a…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Wuhyun Sohn , Andrei Lazanu , Philippe Brax , James R. Fergusson

We develop generalized no-scale supergravity models of inflation, and then study the corresponding cosmological predictions as well as the formation of primordial black holes (PBHs) and scalar-induced gravitational waves (SIGWs). With a new…

General Relativity and Quantum Cosmology · Physics 2024-07-22 Lina Wu , Jin-Ke Shen , Tianjun Li , Junle Pei

In this short note we translate the best available observational bounds on the CMB bispectrum amplitudes into constraints on a specific scale-invariant New Physics Hypersurface (NPH) model of vacuum state modifications, as first proposed by…

High Energy Physics - Theory · Physics 2011-03-23 P. Daniel Meerburg , Jan Pieter van der Schaar

While detection of the "local form" bispectrum of primordial perturbations would rule out all single-field inflation models, multi-field models would still be allowed. We show that multi-field models described by the $\delta N$ formalism…

General Relativity and Quantum Cosmology · Physics 2011-07-28 Naonori S. Sugiyama , Eiichiro Komatsu , Toshifumi Futamase

Attention has focussed recently on models of inflation that involve a second or more fields with a mass near the inflationary Hubble parameter $H$, as may occur in supersymmetric theories if the supersymmetry-breaking scale is not far from…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 Emanuela Dimastrogiovanni , Matteo Fasiello , Marc Kamionkowski

The prediction of a nearly scale-invariant spectrum of curvature and tensor fluctuations is among the main features of cosmic inflation. The current measurements of the primordial fluctuations in the cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-30 Marcos A. G. Garcia , Aline Pereyra-Flores

The present study connects inflation and freeze-in type dark matter (DM) within the same setup. Although the observables in these two phenomena lie at vastly different energy scales, they have been properly handled using the RG running of…

High Energy Physics - Phenomenology · Physics 2025-07-01 Sarif Khan , Sourov Roy , Ananya Tapadar

Using the dS/QFT correspondence in the context of inflation allows for the study of interesting, otherwise inaccessible physics. In particular, by studying inflation via its dual field theory at the boundary of the de Sitter space, it may…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 Mafalda Dias

Based on random matrix theory, we compute the likelihood of saddles and minima in a class of random potentials that are softly bounded from above and below, as required for the validity of low energy effective theories. Imposing this bound…

High Energy Physics - Theory · Physics 2012-06-22 Diana Battefeld , Thorsten Battefeld , Sebastian Schulz

The matter fluctuation parameter $\sigma_8$ is, by model construction, degenerate with the growth index $\gamma$. Here, we study the effect on the cosmological parameter constraints by treating each independently from one another,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-11 Ziad Sakr
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